8.1- THE PERIODIC TABLE Flashcards
What is the periodic table?
list of all elements in order of increasing atomic number
How can you predict the properties of an element from the periodic table?
from its position in the table
What can you use the periodic table to explain? (2)
similarities of certain elements and trends in properties, in terms of their electronic configuration
Two forms that the periodic table had been written in?
spiral and pyramid
On what side are the non-metals on the periodic table?
right
On what side are the metals on the periodic table?
left
What separates the metals and the non-metals on the periodic table?
‘staircase’ line
What are the properties of elements that touch the staircase line on the periodic table like?
have combination of metallic and non-metallic properties
Example of an element that touches the ‘staircase’ line on the periodic table?
silicon
What are elements that touch the ‘staircase’ line on the periodic table called?
metalloids or semi-metals
How is silicon a metalloid/ semi-metal?
it’s a non-metal but it looks quite shiny and conducts electricity, although not as well as a metal
What are s-block elements?
elements that have their highest energy electrons in s-orbitals
What are p-block elements?
elements that have their highest energy electrons in p-orbitals
What are d-block elements?
elements that have their highest energy electrons in d-orbitals
Strictly speaking are transition metals and d-block elements exactly the same?
no
Why are scandium and zinc not transition metals?
they don’t form any compounds in which they have partly filled d-orbitals, which is a characteristic of transition metals
What do elements give out when they are heated?
light energy at certain wavelengths, as excited electrons fall back from one energy level to a lower one
When light energy at certain wavelength are given out when elements are heated what does this cause? (hint spectrum)
line to appear in spectrum of light they give out
What do the letters s, p, d, and f stand for when used to describe lines on spectrum?
- s sharp
- p principal
- d diffuse
- f fine
What is a group on the periodic table?
vertical column of elements
What do elements in the same group form?
chemical family- have similar properties
What do elements in the same group have the same number of?
same number of electrons in the outer main level
In the s-block elements how does reactivity change going down the group?
get more reactive going down the group
On the right of the periodic table how does reactivity change going down the group?
elements tend to get more reactive going up a group
What are the transition metals? (reactivity)
block of rather unreactive metals
Where are most useful metals found?
transition metals block
What are lanthanides?
metals which are not often encountered
What charge ions do lanthanides tend to form in their compounds?
all tend to form +3 ions in their compounds
What is the reactivity of all the lanthanides like?
broadly similar reactivity
What are actinides?
radioactive metals
What are the only actinides that occur naturally in the Earth’s crust in anything more than trace quantities? (2)
thorium and uranium
What are periods in the periodic table?
horizontal rows of elements
What trends are their going across a period?
trends in physical properties and chemical behaviour
Where is helium usually placed above on the periodic table?
above the noble gases
Why is helium usually placed above the noble gases on the periodic table?
because of its properties
Why shouldn’t helium be placed above the noble gases on the periodic table?
it’s not a p-block element- its electronic arrangement is 1s2
Where is hydrogen sometimes placed on the periodic table?
above group 1
Where is hydrogen often placed on the periodic table?
on its own
What is the only way that hydrogen and group 1 elements are similar?
hydrogen usually forms singly charged +1 (H+) ions like group 1 elements
Other than hydrogen and group 1 elements both forming +1 ions, why are group 1 elements and hydrogen not similar?
group 1 elements are reactive metals and hydrogen is a gas
Why is hydrogen sometimes placed above the halogens?
as it can form H- ions and also bond covalently
